A variable resistor would dissipate power as heat and acts as a voltage divider. Modern dimmers are built from semiconductors instead of variable resistors, because they have higher efficiency. Dimmers with direct manual control had a limit on the speed they could be varied at but this problem has been largely eliminated with modern digital units (although very fast changes in brightness may still be avoided for other reasons like lamp life). In the professional lighting industry, changes in intensity are called "fades" and can be "fade up" or "fade down".
In newer systems, these protocols are often used in conjunction with Ethernet. Modern professional dimmers are generally controlled by a digital control system like DMX or DALI.
Small domestic dimmers are generally directly controlled, although remote control systems (such as X10) are available. More specialized equipment is needed to dim fluorescent, mercury vapor, solid-state, and other arc lighting.ĭimmers range in size from small units the size of domestic light switches to high-power units used in large theatrical or architectural lighting installations. Although variable-voltage devices are used for various purposes, the term dimmer is generally reserved for those intended to control light output from resistive incandescent, halogen, and (more recently) compact fluorescent lights (CFLs) and light-emitting diodes (LEDs). By changing the voltage waveform applied to the lamp, it is possible to lower the intensity of the light output. *Base Rate + $1.Dimmers are devices connected to a light fixture and used to lower the brightness of light.Real-Time Rates are calculated for all International shipments.$39.99 Priority Overnight SHIPPING on orders under 2lbs.$29.99 Standard Overnight SHIPPING on orders under 2lbs.$9.99 UPS GROUND SHIPPING on orders under 2lbs.$8.99 FedEx GROUND SHIPPING on orders under 2lbs.$9.99 2-Day SHIPPING on orders under 2lbs.FREE USPS First Class SHIPPING on orders under 13oz.The shipping offered is meant to provide the widest variety of shipping options at the lowest price: See respective ZONE maps below for SPECIFIC delivery time to your location:Īny order that does not qualify for free shipping, will by default include a discount of equal value to the free shipping offer. If your order is NOT shipped the same business day, LEDSupply will offer a 5% discount off your next order. Orders received before 3PM EST will be safely packaged and quickly shipped the same business day. LEDSupply does NOT profit from the shipping or handling of your order! FREE SHIPPING on orders under 13oz - NO MINIMUM
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